ISA Publishes EDDL Standard

The ISA-SP104 committee published “ANSI/ISA-61804-3 (104.00.01)-2007, Function Blocks (FB) for Process Control – Part 3: Electronic Device Description Language (EDDL).” The standard establishes an operating system-independent language used to declare device parameters and their dependencies, device functions, graphical representations, and interactions with control devices. The language, Electronic Device Description Language (EDDL), is used to create an Electronic Device Description (EDD) for intelligent devices to integrate these with control systems and handheld communicators for use in the field. An EDD is a text file, and its use supports information retrieval, diagnostics, performance analysis, operational statistics, parameter handling, operation, range setting, calibration trim, simulation, override, and monitoring of automation system components.

“This standard helps users and integrators fully utilize the EDDL interface to support a wide array of intelligent devices,” said committee chair Terry Blevins, in a prepared statement. “Using tools based on EDDL can mean faster device commissioning and loop checkout, as well as reduced field trips and the elimination of unnecessary maintenance.”

One of the greatest benefits that EDDL provides the process industry is interoperability across multiple hosts, devices and technologies. This flexibility allows the end-user to choose the best combination of price and performance for devices and software. Since an EDD is required for Foundation Fieldbus (FF) device registration, and EDDL is the only device description language supported by the HART Communication Foundation, EDDL is supported by virtually every Process Control Systems vendor worldwide, and EDD”s are available for any FOUNDATION or HART device and for many Profibus-based field device.

EDDL provides a structure for supporting the most simple to the very complex field device. Since EDD”s are text-based files that are interpreted or compiled by the host system, they are independent of operating systems and control platforms. This enables field device additions to be incorporated without affecting the runtime stability of the control system.